P4: PLC for SINUMERIK 828D
14.6 Function interface
Basic Functions
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
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14.6
Function interface
14.6.1
Read/write NC variables
14.6.1.1
User interface
The PLC user program can read or write a maximum of eight variables from the NCK area via the PLC/NCK
interface "Read/write NC variable".
The user interface should be operated as follows:
Job specification
Each of the 1-8 variables that should be processed in a job, must be specified via their parameters in the
variable-specific job interface (from offset 1000).
The general identifiers are discussed in more detail later for each variable that can be accessed from the
interface.
Convention: DB120x: The x should be replaced by 0-7 for 1-8 variables.
Action
See chapter
1
Specify each individual variable to be read or written, for a write job:
Writing the variables
2
Start job
3
Test and wait until "Job completed" or "Error in job"
4
Evaluate the result interface of each individual variable for validity or
error, for read job: Reading variables
5
Reset "start"
DB1200 ...1207 FB2/3
Reading/writing NC data [r/w]
PLC -> NCK interface
Byte
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
DBB 1000
Variable index
DBB 1001
Area number
DBW 1002
Column index for the NCK variable x (WORD)
DBW 1004
Line index for the NCK variable x (WORD)
DBW 1006
DBD 1008
Write: Data to NCK variable x (data type of the variables: 1…4 bytes)
